Bone Scan or 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography; Which Modality Better Shows Bone Metastases of Breast Cancer?

Background

In this multicenter study, we aimed to compare concurrent ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and bone scan results of breast cancer patient.

Patients and Methods

162 patients with breast cancer (158 female, 4 male; mean age 50.6 years) were included in the study. FDG PET/CT examination was performed in all patients, and concurrent bone scintigraphy in 68 patients. The results of FDG PET/CT and bone scan were compared.

Results

132 of the 162 patients were operated on because of breast cancer. 89 patients had metastasis, and 4 had recurrent disease according to FDG PET/CT results. Metastatic sites in order of frequency were lymph nodes, bone, lung, liver, adrenal gland, local skin or muscle, brain, and peritoneum (peritonitis carcinomatosa). The sensitivity, specificity, accuracy, and negative and positive predictive value of bone scintigraphy versus FDG PET/CT were 96 vs. 100%, 100 vs. 98%, 100 vs. 83%, 100 vs. 100%, and 90 vs. 100%, respectively.

Conclusion

Although the 2 modalities were in concordance with each other, in 5 (21%) cases, FDG PET/CT could not show bone metastasis which were detected on bone scintigraphy. Hence, bone scintigraphy was superior to FDG PET/CT in the determination of bone metastasis derived from breast cancer. However, FDG PET/CT should be considered for soft tissue metastasis.     

Significance of 18F‐fluorodeoxyglucose positron‐emission tomography/computed tomography for the postoperative surveillance of advanced renal cell carcinoma

OBJECTIVES

To evaluate the role of ¹⁸F‐fluorodeoxyglucose (FDG) positron‐emission tomography (PET)/computed tomography (CT) for the surveillance of patients with renal cell carcinoma (RCC) who have a high risk of local recurrence or distant metastasis, by comparing the results with those of conventional imaging methods.

PATIENTS AND METHODS

Sixty‐three patients with RCC had conventional imaging studies and FDG PET/CT during the follow‐up after surgical treatment. Their pathological stages were T2 in 28 patients, T3a in 14, T3b in 19 and T4 in two; lymph‐node or distant metastases were present in 12 patients. Suspicious recurrent or metastatic lesions were confirmed by histopathology or by clinical follow‐up. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of conventional surveillance methods and FDG PET/CT were analysed. The difference in the accuracy of FDG PET/CT by nuclear grade and histological subtype of tumours was also assessed.

RESULTS

The FDG PET/CT accurately classified the presence of a recurrence or metastasis in 56 (89%) patients. FDG PET/CT had an 89.5% sensitivity, 83.3% specificity, 77.3% positive predictive value, 92.6% negative predictive value, and 85.7% accuracy in detecting recurrence or metastasis, which was not significantly different from the results with conventional methods. Moreover, the accuracy of the FDG PET/CT by nuclear grade and histological subtypes was not significantly different.

CONCLUSION

For the surveillance of high‐risk RCC, FDG PET/CT had results that were as good as conventional methods and were not influenced by the nuclear grades of cancer cells. In addition, it was possible to examine all organ systems in one procedure, and there was no need for contrast agents, that can damage renal function. Therefore, FDG PET/CT might replace conventional methods.     

The diagnostic accuracy of 18F-fluorodeoxyglucose positron emission tomography and computed tomography in staging bladder cancer: a single-institution study and a systematic review with meta-analysis

Purpose

The purpose of this study was to assess the diagnostic accuracy of 18F-fluorodeoxyglucose with positron emission tomography and computed tomography (FDG–PET–CT) to predict nodal metastases in patients with bladder cancer (BC) scheduled to undergo radical cystectomy (RC).

Methods

We retrospectively reviewed records of patients diagnosed with BC and scheduled to undergo RC at our center from January 2011 through February 2015, who also underwent FDG–PET–CT at the time of diagnosis. All patients underwent RC and an extended pelvic lymph node dissection as the reference standard. The primary endpoints were the sensitivity, specificity and overall accuracy of FDG–PET–CT in detecting lymph node metastasis. We also examined its accuracy in identifying distant metastasis. In addition, we conducted a protocol-driven systematic review and meta-analysis of accuracy of FDG–PET–CT for preoperative staging of BC, as compared to CT alone, as reported in individual studies. To assess the methodological quality of eligible studies, we used the QUADAS-2 tool (a revised tool for the Quality Assessment of Diagnostic Accuracy Studies) and pooled diagnostic accuracy measures using Meta-DiSc statistical software.

Results

For detecting nodal metastases in 78 patients, the sensitivity of FDG–PET–CT was 0.56 (95 % CI 0.29–0.80) and the specificity, 0.98 (95 % CI 0.91–1.00). Pooled sensitivity and specificity for detecting lymph node metastasis were 0.57 and 0.95, respectively. Positive likelihood ratio was 9.02. All lesions that were suspicious for distant metastasis were found to be positive on biopsy.

Conclusion

FDG–PET–CT was more accurate than CT alone in staging BC in patients undergoing surgery. Standardization of FDG–PET–CT protocol and cost-effectiveness analysis are required before widespread implementation of this technology.

     

Combined 18F‐fluorocholine and 18F‐fluoride positron emission tomography/computed tomography imaging for staging of high‐risk prostate cancer

Study Type – Diagnosis (cohort) Level of Evidence 2a What's known on the subject? and What does the study add? Positron emission tomography/computed tomography (PET/CT) with choline and fluoride for the detection of metastases in patients with prostate cancer have each been evaluated, with mixed results. Choline PET/CT has been evaluated against pelvic lymphadenectomy, generally with a low sensitivity but a high specificity; however, the study populations have been heterogenous. Fluoride PET/CT has been evaluated against other imaging methods, such as bone scan, single photon emission CT and MRI, and has been shown to have high specificity as well as sensitivity for bone metastases, but there are no studies with biopsy verification. This is the first study that evaluates the clinical use of both choline and fluoride PET/CT on the same patients in a well‐defined population of patients with high‐risk prostate cancer.

OBJECTIVE

• ? To investigate how often positron emission tomography/computed tomography (PET/CT) scans, with both ¹⁸F‐fluorocholine and ¹⁸F‐fluoride as markers, add clinically relevant information for patients with prostate cancer who have high‐risk tumours and a normal or inconclusive planar bone scan.

PATIENTS AND METHODS

• ? Patients with prostate cancer with prostate specific antigen (PSA) levels between 20 and 99 ng/mL and/or Gleason score 8–10 tumours, planned for treatment with curative intent based on routine staging with a negative or inconclusive bone scan, were further investigated with a ¹⁸F‐fluorocholine and a ¹⁸F‐fluoride PET/CT.
• ? None of the patients received hormonal therapy before the staging procedures were completed.

RESULTS

• ? For 50 of the 90 included patients (56%) one or both PET/CT scans indicated metastases.
• ? ¹⁸F‐fluorocholine PET/CT indicated lymph node metastases and/or bone metastases in 35 patients (39%).
• ? ¹⁸F‐fluoride PET/CT was suggestive for bone metastases in 37 patients (41%).
• ? In 18 patients (20%) the PET/CT scans indicated widespread metastases, leading to a change in therapy intent from curative to non‐curative.
• ? Of the patients with positive scans, 74% had Gleason score 8–10 tumours. Of the patients with Gleason score 8–10 tumours, 64% had positive scans.

CONCLUSIONS

• ? PET/CT scans with ¹⁸F‐fluorocholine and ¹⁸F‐fluoride commonly detect metastases in patients with high‐risk prostate cancer and a negative or inconclusive bone scan.
• ? For 20% of the patients the results of the PET/CT scans changed the treatment plan.

     

Management of urethral recurrence after orthotopic urinary diversion

Study Type – Therapy (case series)
Level of Evidence 4

OBJECTIVE

To evaluate our experience with urethral recurrences in patients treated by radical cystectomy(RC) and orthotopic neobladder urinary diversion for carcinoma of the bladder.

PATIENTS AND METHODS

We retrospectively reviewed the records of patients treated with RC and orthotopic urinary diversion between January 1980 and July 2004.

RESULTS

In all, 260 patients underwent RC with a Studer or Hautmann orthotopic urinary diversion; the median (range) follow‐up was 5.1 (0–15.6) years. Six patients (2.3%) developed local recurrence of urothelial cancer (UC) within the urethra after this treatment. The median (range) time to presentation with recurrence after RC was 2.4 (0.7–3.6) years for pT1‐4 UC. Recurrences were treated with various methods, including transurethral resection, urethrectomy with conversion of neobladder to continent catheterizable diversion, and chemotherapy. At the last follow‐up, four of these six patients were alive without disease, one was alive with disease, and one had died from disease.

CONCLUSIONS

In our experience, local recurrences involving the urethra are infrequent. Complete surgical excision can provide a good outcome. Neoadjuvant chemotherapy should be considered for recurrences with adverse clinicopathological features.     

Diagnostic efficacy of [11C]choline positron emission tomography/computed tomography compared with conventional computed tomography in lymph node staging of patients with bladder cancer prior to radical cystectomy

Background

Current imaging techniques are of limited value for lymph node (LN) staging in bladder cancer (BCa) patients scheduled for radical cystectomy (RC).

Objective

Evaluate the diagnostic efficacy of [11C]choline positron emission tomography in combination with computed tomography (PET/CT) for LN staging of patients with BCa scheduled for RC and compare that efficacy with the diagnostic efficacy of CT and the gold standard of histopathologic evaluation.

Design, setting, and participants

From June 2004 to May 2007, 44 patients with localized BCa were staged with [11C]choline PET with low-dose CT for attenuation correction and simultaneous intravenous and rectal contrast-enhanced diagnostic CT before RC and pelvic lymph node dissection (PLND). LNs were dissected from the internal and external iliac arteries up to the origin of the inferior mesentery artery according to a template with 14 predefined anatomic fields.

Intervention

Diagnostic [11C]choline PET/CT before RC and regional LN dissection.

Measurements

Histopathologic findings of resected LN were correlated with the results of [11C]choline PET/CT and CT alone in a patient- and field-based manner. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of [11C]choline PET/CT and CT were assessed.

Results and limitations

LN metastases were found in 12 of 44 patients (27%). On patient-based analysis, sensitivity, specificity, PPV, NPV, and accuracy for [11C]choline PET/CT were calculated as 58%, 66%, 39%, 81%, and 64%, respectively; and for CT the calculated percentages were 75%, 56%, 39%, 86%, and 61%, respectively. Twenty-five of 471 dissected LN fields (5%) showed metastases. On field-based analysis, sensitivity, specificity, PPV, NPV, and accuracy for [11C]choline PET/CT were 28%, 95%, 21%, 96%, and 91%, respectively; for CT, the calculated percentages were 39%, 92%, 20%, 96%, and 90%, respectively. Limitations of this study are small patient number and the fact that not all patients underwent extensive PLND.

Conclusions

In patients with BCa who were scheduled for RC, preoperative LN staging with [11C]choline PET/CT was not able to improve diagnostic efficacy compared with conventional CT alone.     

Survival after radical cystectomy of non-bilharzial squamous cell carcinoma vs urothelial carcinoma: a competing-risks analysis

Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? To date, there is controversy about the impact of histological subtype of bladder cancer (nonbilharzial squanous cell carcinoma vs. urothelial carcinoma) on cancer control outcomes. Our study shows that the histological subtype may have an impact on the stage of bladder cancer at presentation. However, after adjusting to stage, the histological subtype has no impact on cancer control outcomes.

OBJECTIVES

• ? To test the effect of histological subtype (NBSCC vs UC) on cancer‐specific mortality (CSM), after adjusting for other‐cause mortality (OCM).
• ? In Western countries, non‐bilharzial squamous cell carcinoma (NBSCC) is the second most common histological subtype in bladder cancer (BCa) after urothelial carcinoma (UC).

PATIENTS AND METHODS

• ? We identified 12 311 patients who were treated with radical cystectomy (RC) between 1988 and 2006, within 17 Surveillance, Epidemiology and End Results (SEER) registries.
• ? Univariable and multivariable competing‐risks analyses tested the relationship between histological subtype and CSM, after accounting for OCM.
• ? Covariates consisted of age, sex, year of surgery, race, pathological T and N stages, as well as tumour grade.

RESULTS

• ? Histological subtype was NBSCC in 614 (5%) patients vs UC in 11 697 (95%) patients.
• ? At RC, the rate of non‐organ confined (NOC) BCa was higher in NBSCC patients than in their UC counterparts (71.7% vs 52.2%; P < 0.001).
• ? After adjustment for OCM, The 5‐year cumulative CSM rates were 25.0% vs 19.8% (P= 0.2) for patients with NBSCC vs UC organ confined (OC) BCa, respectively. The same rates were 46.3% vs 49.3% in patients with NOC BCa (P= 0.1).
• ? In multivariable competing‐risks analyses, histological subtype (NBSCC vs UC) failed to achieve independent predictor status of CSM in patients with OC (hazard ratio, 1.2; P= 0.06) or NOC BCa (hazard ratio, 1.1; P= 0.1).

CONCLUSIONS

• ? At RC, the rate of NOC BCa is higher in NBSCC patients than in their UC counterparts.
• ? Despite a more advanced stage at surgery, NBSCC histological subtype is not associated with a less favourable CSM than UC histological subtype, after accounting for OCM and the extent of the disease (OC vs NOC).

     

Beurteilung von Residualtumoren nach Systemtherapie des metastasierten Seminoms

Background

Meta-analysis evaluating the accuracy and sensitivity of FDG (2-[¹⁸F]-fluoro-2-deoxy-D-glucose) positron emission tomography (PET) to predict viable residual tumours in patients with metastatic seminoma.

Material and methods

Altogether 5 studies with 130 patients were identified. Both FDG PET and the size of the residual lesions on conventional computed tomography (CT; lesions either ?? or > 3 cm) were correlated with the presence or absence of viable residual tumour.

Results

The specificity (92 vs 59%), sensitivity (72 vs 63%), positive (70 vs 28%) and negative (93 vs 86%) predictive value of FDG PET were superior to data obtained by assessing residual tumour size (either ?? or > 3 cm) applying CT scans alone.

Conclusion

In view of the data currently available, FDG PET seems to be a clinically useful predictor of viable tumour in post-chemotherapy residuals of pure seminoma.     

Radical cystectomy for urothelial carcinoma of the bladder: an analysis of perioperative and survival outcome

OBJECTIVE

To review the outcomes in a large group of patients treated with radical cystectomy (RC) for urothelial cancer (UC) of the bladder, by one surgical team.

PATIENTS AND METHODS

In all, 504 patients had RC for UC of the bladder between 1992 and 2007; 432 met the inclusion criteria and were analysed for survival and disease recurrence.

RESULTS

Of the 432 patients, (mean age 69 years; mean follow‐up 38 months, range 1–172), 240 (56%) and 179 (41%) had an ileal conduit and orthotopic neobladder for urinary diversion, respectively. The mortality rate within 30 days of RC was 2%; 105 (24%) patients developed local and/or distant recurrence with a mean interval of 13.6 months. The overall survival, recurrence‐free survival (RFS) and disease‐specific survival (DSS) at 5 years was 58%, 64% and 74%, respectively, and 43%, 62% and 68% at 10 years. The 5‐year RFS and DSS for those with organ‐confined, node‐negative tumours was 81% and 91%, compared to 46% and 56% in those with extravesical extension and lymph node‐negative tumours. The RFS and DSS of patients with lymph node metastasis at 5 years was 29% and 40%, respectively.

CONCLUSION

Our study reaffirms that RC with bilateral pelvic lymph node dissection offers a reasonable possibility of disease control at 5 years, with a DSS of 74%. However, there is a need for an earlier diagnosis and effective systemic therapy if additional gains in survival are to be delivered.     

Outcomes following radical cystectomy for micropapillary bladder cancer versus pure urothelial carcinoma: a matched cohort analysis

Purpose

Micropapillary (MP) bladder cancer is a rare variant of urothelial carcinoma (UC) which has been associated with an aggressive natural history. We sought to report the outcomes of patients with MP bladder cancer treated with radical cystectomy (RC) and compare survival to patients with pure UC of the bladder.

Methods

We identified 73 patients with MP bladder cancer and 748 patients with pure UC who underwent RC at our institution with median postoperative follow-up of 9.6?years. MP patients were stage-matched 1:2 to patients with pure UC. Survival was estimated using the Kaplan?CMeier method and compared with the log-rank test.

Results

MP cancers were associated with a high rate of adverse pathologic features, as 48/73 patients (66?%) had pT3/4 tumors and 37 (50?%) had pN+ disease. Ten-year cancer-specific survival in MP patients was 31?%, compared with 53?% in the overall cohort with pure UC (p?=?0.001). When patients with MP bladder cancer were then stage-matched to those with pure UC, no significant differences between the groups were noted with regard to 10-year local recurrence-free survival (62 vs. 69?%; p?=?0.87), distant metastasis-free survival (44 vs. 56?%; p?=?0.54), or cancer-specific survival (31 vs. 40?%; p?=?0.41).

Conclusion

MP cancers are associated with a higher rate of locally advanced disease. However, when matched to patients with pure UC, patients with MP tumors did not have increased local/distant recurrence or adverse cancer-specific survival following RC.     

Lymphovascular invasion is an independent predictor of oncological outcomes in patients with lymph node‐negative urothelial bladder cancer treated by radical cystectomy: a multicentre validation trial

Study Type – Prognosis (inception cohort)
Level of Evidence 1b

OBJECTIVES

To validate the association of lymphovascular invasion (LVI) with disease recurrence and cancer‐specific survival (CSS) in a multicentre cohort of patients treated with radical cystectomy (RC) for urothelial bladder cancer (UBC).

PATIENTS AND METHODS

We collected pathological and clinical data on 1099 lymph node‐negative patients treated with RC at six German institutions. LVI was defined as the presence of tumour cells within an unequivocal endothelium‐lined space in haematoxylin and eosin‐stained sections.

RESULTS

LVI was present in 295 (26.8%) patients; the presence of LVI correlated significantly with increasing tumour stage, i.e. pT1, 65 (29.4%); pT2, 88 (31.5%); pT3 110 (31.8%); and pT4 32 (38.1%) (P= 0.002) and grade (P < 0.001). In univariable analysis the presence of LVI was significantly associated with reduced recurrence‐free survival (P= 0.008) and reduced CSS (P= 0.039). On multivariable Cox regression analysis tumour stage (P < 0.001), age (>75 vs ≥75 years; P= 0.018) and LVI (P < 0.001) were identified as independent predictors of CSS.

CONCLUSIONS

Our large multicentre study confirms the independent prognostic value of LVI in patients with node‐negative UBC. LVI can be regarded as a surrogate variable for lymphatic micrometastasis in node‐negative UBC. Assessment of LVI might improve the selection of patients who are likely to benefit from adjuvant therapy after RC. The identification of factors involved in the process of LVI could reveal new therapeutic targets for UBC.     

Prognostic significance of tumor location and superficial urothelial bladder carcinoma history in patients with ureteral urothelial carcinoma treated with radical nephroureterectomy

Purpose

To investigate the significance of tumor location and superficial urothelial bladder carcinoma (UBC) history on oncological outcomes in patients treated with radical nephroureterectomy (RNU) for ureteral urothelial carcinoma (UC).

Methods

One hundred and thirty-two patients treated with RNU for ureteral UC between January 1999 and July 2010 were retrospectively analyzed. Recurrence probabilities and survival rates were analyzed, stratified by tumor location and superficial UBC history.

Results

Comparison of patients with proximal, middle, and distal ureteral UC showed that percentage of bladder recurrence was 13.3, 14.7, and 25.0 %, respectively (P = 0.285); retroperitoneal (tumor bed or lymph node) recurrence was 26.7, 14.7, and 27.9 % (P = 0.319); and contralateral recurrence was 0, 2.9, and 0 % (P = 0.234). Comparison of patients with and without history of superficial UBC revealed that percentage of bladder recurrence was 15.4 and 20.2 %, respectively (P = 0.681); retroperitoneal recurrence was 15.4 and 25.2 % (P = 0.433); and contralateral recurrence was 0 and 0.84 % (P = 0.740). Using multivariable Cox regression analyses, there were no significant differences of recurrence-free survival (RFS) and cancer-specific survival (CSS) with regard to neither tumor location nor superficial UBC history (RFS: P = 0.282 and 0.762, CSS: P = 0.272 and 0.818, respectively).

Conclusions

Tumor location and history of superficial UBC could not be used to predict oncological outcomes of patients who underwent RNU for ureteral UC. Therefore, operative strategies or postoperative surveillance should not be affected by tumor location or history of superficial UBC.     

Clinical significance of lymphovascular invasion in upper urinary tract urothelial cancer

OBJECTIVES

To clarify the significance of lymphovascular invasion (LVI) in patients with pT3N0M0 upper urinary tract (UUT) urothelial carcinoma (UC) relative to prognosis in terms of disease‐specific survival, as LVI, which implies both blood vessel and lymph vessel involvement, is reportedly a poor prognostic factor in patients with UUT‐UC.

PATIENTS AND METHODS

The clinical records of 90 patients who had surgery for UUT‐UC were reviewed retrospectively. The median patient age was 71 years and the median follow‐up was 42 months. The prognostic significances of LVI (with vs without), T stage (<1 vs 2–4), grade (1–2 vs 3), N stage (0 vs 1–2), age (≤70 vs >70 years), gender and tumour location (renal pelvis vs ureter) for survival time were evaluated.

RESULTS

LVI of UUT‐UC was found in 34 patients (37.8%). There were significantly higher frequencies of LVI with advancing stage and lymph node metastasis. Kaplan‐Meier analysis showed that LVI was strongly associated with disease‐specific survival in all patients (P < 0.001) and in patients with pT3N0M0 disease (P < 0.001). Univariate analyses showed that LVI, T stage, N stage and tumour grade were significantly related to disease‐specific survival in all patients (P < 0.001, <0.001, 0.003 and 0.007, respectively). Multivariate analysis using Cox proportional hazards model showed that LVI was the only prognostic factor with independent significance for disease‐specific survival (P < 0.001).

CONCLUSIONS

LVI appears to be an important and independent prognostic factor for UUT‐UC in patients treated by nephroureterectomy. Our data suggest that the LVI status might be a predictive marker for disease‐specific survival in patients with T3N0M0 UTT‐UC.     

18F‐FDG‐PET/CT predicts early tumor recurrence in living donor liver transplantation for hepatocellular carcinoma

The prognosis including ¹⁸F‐fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F‐FDG‐PET/CT) for the early recurrence for hepatocellular carcinoma (HCC) after living donor liver transplantation (LDLT) was not well established. Consecutive patients who underwent ¹⁸F‐FDG‐PET/CT and subsequent LDLT for HCC from March 2005 to June 2011 were enrolled. The 191 patients with a median follow‐up of 26.1 months were evaluated. There were 20 patients (10.5%) with early recurrence (≤6 months), 18 patients (9.4%) with late recurrence (>6 months), and 153 patients (80.1%) with no recurrence. Fifty‐five patients (28.8%) displayed increased PET/CT tumor uptake. Three‐year overall and disease‐free survival for PET/CT‐positive patients were 65.5% and 57.1%, respectively, while PET/CT‐negative patients showed respective values of 89.8% and 86.8% (P = 0.001 vs. P < 0.001). Tumor variables associated with PET/CT‐positive finding were preoperative AFP level, Milan, UCSF criteria, maximum tumor size, total tumor size, differentiation, vascular invasion, and serosal invasion. PET/CT‐positive status was identified as an independent prognostic factor for disease‐free survival influencing early recurrence in multivariable analysis (HR 3.945, 95% CI 1.196–13.016, P = 0.024). ¹⁸F‐FDG‐PET/CT is an independent and significant predictor of early tumor recurrence in LDLT for HCC.     

Detection of incidental colorectal tumours with 18F‐labelled 2‐fluoro‐2‐deoxyglucose positron emission tomography/computed tomography scans: results of a prospective study

Aim This study assessed the clinical significance of incidental colorectal 2‐fluoro‐2‐deoxyglucose (FDG) uptake using ¹⁸F‐FDG positron emission tomography/computed tomography (PET/CT) scans and evaluated the importance of colonoscopy when incidental colorectal FDG uptake was observed. Method A prospective study was designed and conducted at a single institution over a 2‐year period. In patients undergoing PET/CT scans, all with FDG uptake in the colorectum were assigned to have colonoscopy and biopsy. The value of PET/CT scanning was studied by comparison with the colonoscopy and biopsy results. Results Among 10 978 PET/CT scans, one or more focal uptakes of FDG in the colorectum were observed in 148 (1.35%) patients. In 136 valid patients, malignant colorectal tumours and polyps were found in 23.5% and 20.5%, respectively,, while the colon in the other 56% was normal. A higher false‐positive rate was found in the right colon compared with the distal colorectum (66.2%vs 36.7%, P = 0.004). A significant increase of the maximum standardized uptake (SUVmax) value was found among normal, polyps and cancer groups. Multivariate analysis revealed that SUVmax was the risk factor for predicting colorectal cancer or polyps and FDG uptake in the right colon was a negative predictive factor for finding cancers or polyps. Conclusions Our study proves the necessity of colonoscopy when incidental FDG uptake is found on PET/CT imaging. The false‐positive FDG uptake is more commonly observed in the right colon. Although the SUVmax value is higher in cancer patients, a high SUVmax value does not necessarily result in malignancies.     

Comparison of the new American Joint Committee on Cancer substratification in node-negative pT2 urothelial carcinoma of the bladder: analysis of patient outcomes in a contemporary series

Study Type – Prognosis (case series) Level of Evidence 4 What’s known on the subject? and What does the study add? The prognostic value of pathological substratification in lymph node‐negative pT2 urothelial carcinoma of the bladder based on tumour depth has been controversially discussed in recent studies. In 1997, the AJCC and UICC modified the TNM staging system in bladder cancer providing a new substratification in pT2 bladder cancer based on a previous study of Jewett in 1952 reporting a worse prognosis for patients with deep muscle invasion compared to those with superficial muscle invasion. Recently, this prognostic significance has been considered of minor importance compared to significance of lymph node tumor involvement. Thus, many of these studies concluded that future revisions of the TNM staging system should consolidate both substages. However, these studies were hampered by the inclusion of patients with non‐urothelial carcinoma components, unknown number of retrieved lymph nodes, unknown extent of pelvic lymphadenectomy, and inclusion of patients undergoing neoadjuvant chemotherapy. This study addresses specifically the prognostic significance of pT2 substaging in urothelial cancer in a contemporary, consecutive series of patients treated with radical cystectomy. All patients had pure urothelial cell carcinoma, and underwent an extended lymphadenectomy approach. The number of retrieved lymph nodes was recorded. There was a significant difference in survival in patients with lymph‐node negative pT2a vs. pT2b disease. Therefore, this study supports the prognostic value of the current substratification in pT2 urothelial carcinoma of the bladder.

OBJECTIVE

? To determine whether there is a difference in survival in patients with node‐negative pT2a vs pT2b urothelial carcinoma of the bladder (UBC), as recent studies suggest that the new American Joint Committee on Cancer substratification may not have prognostic significance.

PATIENTS AND METHODS

? Of 252 patients undergoing radical cystectomy (RC) and extended bilateral pelvic lymphadenectomy (ePLND) between 1999 and 2009, 72 (28.6%), with a mean (range) age of 66 (44–83) years (50 men, 22 women), had pathologically confirmed pT2 UCB. ? Fisher’s exact test and Cox regression analysis were used for uni‐ and multivariate analysis of risk factors of recurrence at a median (range) follow‐up of 28 (2.2–115.7) months. ? Kaplan–Meier plots were used to estimate the impact of pT2 substratification in lymph node (LN)‐negative disease on recurrence‐free (RFS) and cancer‐specific (CSS) survival using log‐rank test.

RESULTS

? Of the 72 patients, 39 had pT2a (54.2%) and 33 pT2b UCB (45.8%) on definitive histological examination. The median (range) number of LNs removed was 19 (6–38) in pT2a and 22 (4–36) in pT2b (P = 0.31) UCB. ? At RC, there was LN‐positive disease in one patient with pT2a UCB, whereas seven patients with pT2b UCB had LN‐positive disease (P = 0.02). ? The median (range) number of LNs removed in LN‐positive disease was 18 (11–30) and in LN‐negative disease was 20 (4–38) (P = 0.52). ? In LN‐negative disease, actuarial 5‐year RFS was 85.9% in patients with pT2a UCB vs 37.5% in those with pT2b UCB (P < 0.001). Actuarial 5‐year CSS was 84.8% in patients with LN‐negative pT2a UCB vs 59.6% in patients with LN‐negative pT2b UCB (P = 0.01). ? In Cox regression analysis, pT2 substratification was the only independent risk factor of recurrence and cancer‐specific death (P < 0.001 and P = 0.008).

CONCLUSIONS

? In this contemporary series of patients undergoing RC with ePLND, there was a significant difference in RFS and CSS between LN‐negative pT2a and pT2b UCB, and pT2 substratification was the only risk factor of recurrence and cancer‐specific death. ? These data are supportive of the current concept of substratification in LN‐negative pT2 UCB.     

Staging fluorodeoxyglucose positron emission tomography/computed tomography for muscle-invasive bladder cancer: a nationwide population-based study

Objective

To provide insight into the use and staging information on lymph-node involvement added by fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) in patients with muscle-invasive bladder cancer (MIBC), based on a nationwide population-based cohort study.

Patients and methods

We analysed a nationwide cohort of patients with MIBC without signs of distant metastases, newly diagnosed in the Netherlands between November 2017 and October 2019. From this cohort, we selected patients who underwent pre-treatment staging with CT only or CT and FDG-PET/CT. The distribution of patients, disease characteristics, imaging findings, nodal status (clinical nodal stage cN0 vs cN+) and treatment were described for each imaging modality group (CT only vs CT and FDG-PET/CT).

Results

We identified 2731 patients with MIBC: 1888 (69.1%) underwent CT only; 606 (22.2%) underwent CT and FDG-PET/CT, 237 (8.6%) underwent no CT. Of the patients who underwent CT only, 200/1888 (10.6%) were staged as cN+, vs 217/606 (35.8%) who underwent CT and FDG-PET/CT. Stratified analysis showed that this difference was found in patients with clinical tumour stage (cT)2 as well as cT3/4 MIBC. Of patients who underwent both imaging modalities and were staged with CT as cN0, 109/498 (21.9%) were upstaged to cN+ based on FDG-PET/CT. Radical cystectomy (RC) was the most common treatment within both imaging groups. Preoperative chemotherapy was more frequently applied in cN+ disease and in FDG-PET/CT-staged patients. Concordance of pathological N stage after upfront RC was higher among patients staged as cN+ with CT and FDG-PET/CT (50.0% pN+) than those staged as cN+ with only CT (39.3%).

Conclusion

Patients with MIBC who underwent pre-treatment staging with FDG-PET/CT were more often staged as lymph node positive, regardless of cT stage. In patients with MIBC who underwent CT and FDG-PET/CT, FDG-PET/CT led to clinical nodal upstaging in approximately one-fifth. Additional imaging findings may influence subsequent treatment strategies.     

Incidental focal colonic lesions found on 18Fluorodeoxyglucose positron emission tomography/computed tomography scan: further support for a national guideline on definitive management

Aim ¹⁸Fluorodeoxyglucose (¹⁸FDG) positron emission tomography/computed tomography (PET/CT) is an established part of staging in a wide variety of malignancies. Incidental abnormal uptake of ¹⁸FDG of unknown significance is frequently encountered. Therefore, we investigated patients with abnormal colonic uptake of ¹⁸FDG, determined by PET/CT images, using colonoscopy. Method The radiology reports of all patients referred to a tertiary referral centre for a PET/CT scan were reviewed retrospectively. Patients with abnormal colonic uptake of ¹⁸FDG were identified and the PET/CT findings were correlated with colonoscopic findings. Results Of 555 consecutive patients identified over a 26‐month period, 53 had abnormal colonic uptake of ¹⁸FDG, as determined by PET/CT images. Twenty‐nine were not investigated following discussion in a specialist multidisciplinary (MDT) meeting, according to local protocol. Twenty out of 24 patients investigated by endoscopy had a colonic lesion correlating to the site identified on the PET/CT image: 16 patients had tubulovillous adenomas (nine of which were > 10 mm), two had invasive adenocarcinomas, two had diverticular disease and one had collagenous colitis; no colonic lesion was detected in three. These findings were incidental and not related to the primary diagnosis for which the scan was being performed. Accordingly, a positive predictive value of 83% is associated with the finding of abnormal uptake of ¹⁸FDG on PET/CT images. Conclusion Incidental abnormal colonic uptake of ¹⁸FDG, determined by a PET/CT scan requires definitive colonic investigation in patients suitable for further treatment because significant colonic pathology is frequently identified. The benefit of this approach should be discussed in specialist MDT meetings and tailored to each patient; however, national guidelines for management are required.     

Good quality white-light transurethral resection of bladder tumours (GQ-WLTURBT) with experienced surgeons performing complete resections and obtaining detrusor muscle reduces early recurrence in new non-muscle-invasive bladder cancer: validation across time and place and recommendation for benchmarking

Study Type – Diagnostic (exploratory cohort) Level of Evidence 2a What's known on the subject? and What does the study add? Staging of patients with prostate cancer is the cornerstone of treatment. However, after curative intended therapy a high portion of patients relapse with local and/or distant recurrence. Therefore, one may question whether surgical lymph node dissection (LND) is sufficiently reliable for staging of these patients. Several imaging methods for primary LN staging of patients with prostate cancer have been tested. Acceptable detection rates have not been achieved by CT or MRI or for that matter with PET/CT using the most common tracer fluoromethylcholine (FCH). Other more recent metabolic tracers like acetate and choline seem to be more sensitive for assessment of LNs in both primary staging and re‐staging. However, previous studies were small. Therefore, we assessed the value of [¹⁸F]FCH PET/CT for primary LN staging in a prospective study of a larger sample and with a ‘blinded’ review. After a study period of 3 years and >200 included patients, we concluded that [¹⁸F]FCH PET/CT did not reach an optimal detection rate compared with LND, and, therefore, it cannot replace this procedure. However, we did detect several bone metastases with [¹⁸F]FCH PET/CT that the normal bone scans had missed, and this might be worth pursuing.

OBJECTIVES

• ? To assess the value of [¹⁸F]fluoromethylcholine (FCH) positron emission tomography/computed tomography (PET/CT) for lymph node (LN) staging of prostate cancer.
• ? To evaluate if FCH PET/CT can replace LN dissection (LND) for LN staging of prostate cancer, as about one‐third of patients with prostate cancer who receive intended curative therapy will have recurrence, one reason being undetected LN involvement.

PATIENTS AND METHODS

• ? From January 2008 to December 2010, 210 intermediate‐ or high‐risk patients had a FCH PET/CT scan before regional LND.
• ? After dissection, the result of histological examination of the LNs (gold standard) was compared with the result of FCH PET/CT obtained by ‘blinded review’.
• ? Sensitivity, specificity, positive (PPV), and negative predictive values (NPV) of FCH PET/CT were measured for detection of LNe metastases.

RESULTS

• ? Of the 210 patients, 76 (36.2%) were in the intermediate‐risk group and 134 (63.8%) were in the high‐risk group. A medium (range) of 5 (1–28) LNs were removed per patient.
• ? Histological examination of removed LNs showed metastases in 41 patients. Sensitivity, specificity, PPV, and NPV of FCH PET/CT for patient‐based LN staging were 73.2%, 87.6%, 58.8% and 93.1%, respectively.
• ? Corresponding values for LN‐based analyses were 56.2%, 94.0%, 40.2%, and 96.8%, respectively.
• ? The mean diameter of the true positive LN metastases was significantly larger than that of the false negative LNs (10.3 vs 4.6 mm; P < 0.001).
• ? In addition, FCH PET/CT detected a high focal bone uptake, consistent with bone metastases, in 18 patients, 12 of which had histologically benign LNs.

CONCLUSIONS

• ? Due to a relatively low sensitivity and a correspondingly rather low PPV, FCH PET/CT is not ideal for primary LN staging in patients with prostate cancer.
• ? However, FCH PET/CT does convey important additional information otherwise not recognised, especially for bone metastases.

     

The value of 18F‐FDG PET/CT in diagnosing and localising deep sternal wound infection to guide surgical debridement

Deep sternal wound infection (DSWI) is a severe complication in patients after open heart surgery (OHS). But there is a lack of appropriate imaging tool to detect the infection sites, which may lead to incomplete debridement. The present study aims to investigate the value of ¹⁸F‐fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F‐FDG PET/CT) in comparison with CT scan in diagnosing and localising DSWI. A total of 102 patients with DSWI after OHS were retrospectively collected from January 2012 to December 2017 in our hospital. All the patients had surgical debridements for DSWI with pretreatment imaging of either ¹⁸F‐FDG PET/CT or CT scan. The sensitivity, specificity, and accuracy of localising infection sites were compared between PET/CT and CT groups, with surgical, microbiological, and histopathological findings as the gold standard. The length of hospital stays and the rate of recurrence were also compared. Ten patients in the PET/CT group had a follow‐up PET/CT scan after debridement, and the correlations between the changes of PET/CT findings and surgical outcomes were analysed. ¹⁸F‐FDG PET/CT is more accurate than CT in diagnosing and localising DSWI after OHS, which leads to a more successful surgical debridement with a lower rate of recurrence and a shorter length of hospital stay. In addition, follow‐up PET/CT after debridement could evaluate the treatment effect.